1. Field of the Invention
The present invention relates to a wiping device for an applicator unit. The applicator unit includes a container in which an applicator can be inserted. The wiping device wipes the applicator as the applicator moves in and out of the container. The wiping device can be particularly advantageous for use in the field of cosmetics, but can also be used in other fields where a wiping type applicator is desirable.
2. Description of the Background
A conventional applicator unit includes a container formed by a body defining an end wall and another end opposite to the end wall. The end opposite to the end wall forms a neck. A free edge of the neck delimits an opening. The body is typically cylindrical. Such a conventional unit also includes an applicator. The applicator includes an applicator member, for example, a mascara brush or an eyeliner, one end of which is secured to a rod. The rod is secured to a stopper configured to removably plug the opening of the container. The stopper forms a member which can be used to grasp the applicator member. When the stopper has been screwed onto the container, the applicator member is immersed in the product contained in the container.
Arranged in the neck of the container is a wiping device, for example, in the form of an annular member. The applicator member passes through the annular member both when the applicator member is introduced into the container through the opening and when the applicator member is withdrawn. The wiping device includes a wiping part in the form, for example, of an annular lip. The applicator member engages one edge of the annular lip. The rod connecting the applicator member to the stopper can also engage the annular lip. Thus, the amount of product remaining on the applicator member can be metered or dosed relatively precisely so as to prevent or reduce the amount excess product present on the applicator member. Furthermore, the rod can be wiped when withdrawing the applicator from the container so that the user's fingers do not get dirty when applying the product.
For certain applications, it is useful to use a wiping device with a wiping part made of an elastically deformable material, for example, natural or synthetic rubber. This is the case, for example, for applicators with a cross section that varies appreciably over its length, for applicators configured to pick up a small amount of product, and for applicators with a small cross section relative to the rod. A wiping device made of such an elastically deformable material is described in U.S. Pat. No. 4,617,948. The wiping device disclosed in that patent is placed on an internal edge of the container, and held in place by an additional part forming a threaded neck. Such an arrangement, by entailing that the container be made in two parts, increases the number of assembly operations and raises the manufacturing cost of the unit.
FIGS. 1A and 1B illustrate a conventional wiping device 1. The wiping device 1 is made of elastomer and is configured to fit into a container. Such a wiping device 1 includes a body 2 of cylindrical overall shape. The body 2 and the neck of the container can be formed as a single piece. One of the ends of the body 2 terminates in a rim 3 configured to bear against the edge of a container. A bulge 4 is formed near the rim 3 to improve the seal between the container and the wiping device 1. Near the opposite end of the rim 3, the wiping device ends in an internal edge 5 of reduced section by comparison with the section of the body 2. The edge 5 forms a wiping member. On the outside of the body 2, the wiping device 1 forms a solid bulge 6 configured to secure the wiping device 1 to the container. Once the bulge 6 has entered the neck of the container, the bulge 6 is configured to position itself behind the shoulder of the container, thus immobilizing the wiping device 1 in a position such that the wiping device I is secured to the container.
Because of the elastically deformable nature of the material of which the wiping device 1 is formed, the bulge 6 has to have sufficient radial width (typically of the order of a millimeter) to secure the wiping device 1 firmly to the container. Such a system presents a drawback because the bulge 6 renders the insertion of the wiping device into the neck of the container difficult. The insertion is particularly difficult when performed using an industrial tool. In practice, such an industrial tool can include a rod introduced into the wiping device 1. The wiping device 1 is positioned above the neck of the container, and is pushed in the container in response to pressure exerted axially on the rod. Experience shows that the high resistance generated by the bulge 6 can cause the fitting tool to damage the wiping device 1. Similar wiping devices with one or more relatively “solid” bulges are also described in U.S. Pat. No. 5,884,634 and U.S. Pat. No. 5,875,791.